Antibiotics and Antibacterials: How Much Is Too Much?

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Warning: Your antibacterial hand soap may be doing you more harm than good. Join us as we talk to a germ expert about the ways that antibacterial products and antibiotic medicines create bacteria that are difficult to control. Learn what you can do to help out.

We’re joined by Dr. Stuart Levy, director of the Center for Adaptation Genetics and Drug Resistance at the Tufts University School of Medicine in Boston. He is author of the book, “The Antibiotic Paradox: How the Misuse of Antibiotics Destroys Their Curative Powers.”

As always, our expert guests answer questions from the audience.

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The opinions expressed on this webcast are solely the views of our guests. They are not necessarily the views of HealthTalk, our sponsors or any outside organization. And, as always, please consult your own physician for the medical advice most appropriate for you.

Judy Foreman:

Hello and welcome to HealthTalk Live [HealthTalk Live has been renamed Health Now with Judy Foreman]. I'm your host, Judy Foreman. Just today all 21 school buildings in one county in Virginia were being sanitized after the death of a 17-year-old student from a drug-resistant strain of staph bacteria. Also this week, the Journal of the American Medical Association published a report from the Federal Centers for Disease Control and Prevention showing that 19,000 Americas died in 2005 from a drug-resistant bacterium called MRSA.

The study is shocking because it shows how prevalent this antibiotic-resistant bacterium is. Frighteningly, we've become accustomed to believing that antibiotics will always be there, that they'll always work and that they'll always protect us. But this is not the case. Tonight we will talk about what antibiotics can and can't do, when you should ask for them and when you should tough out an infection without them.

I'm very pleased to welcome tonight Dr.Stuart Levy, director of the Center for Adaptation Genetics and Drug Resistance at the Tufts University School of Medicine in Boston. He is also the author of the book, "The Antibiotic Paradox: How the Misuse of Antibiotics Destroys Their Curative Powers," and he is also president of the International Alliance for the Prudent Use of Antibiotics.

Dr. Stuart Levy, welcome to HealthTalk Live.

Dr. Stuart Levy:

Delighted to be with you.

Judy:

We're very glad to have you. So let's start by briefly defining what a bacterium is and how it's different from a virus.

Dr. Levy:

Okay. A bacterium is a single cell that exists on its own but usually multiplies so quickly that you really have quantities of bacterium called bacteria, the bacterium is the single. It has a single chromosome. It's about a thousand-fold smaller than a cell in our body, and it is able to do everything on its own. A virus is a thousand-fold even smaller, and it cannot multiply on its own. It has to get into a real cell, and then it takes over the machinery of the cell to make the proteins and all the requirements it needs to then burst the cell and become the result of that infection.

Judy:

Okay. And for the record, tell us how many different kinds of bacteria there are.

Dr. Levy:

There are millions of different strains of bacteria, and we're still discovering more now in distant places, deep, 10,000 feet in the earth, in caves, down deep in the ocean, extreme temperatures, very cold, very hot. It's an amazing world we live in, but bacteria have certainly populated it with a variety that we don't see, and it's pretty difficult for us to see what they can do in these extreme environments.

Judy:

And they got here before we did by a long shot, didn't they?

Dr. Levy:

Very much so.

Judy:

So what is the difference between the bad bacteria and the so-called probiotics, the good bacteria?

Dr. Levy:

We, every day, are in contact with other bacteria that are not going to cause disease. In fact on our skin, in our intestinal tract, our throat, we have bacteria. We need them. We need them in the intestinal tract to help digest the food and produce vitamins that we rely on. But otherwise these bacteria also protect us from the so-called bad bacteria, those that can produce toxins, those that can destroy tissue and make you sick. These bacteria fortunately are in the minority.

Judy:

The bad ones.

Dr. Levy:

The bad ones. The other bacteria, the ones that we call good, some people call them commensal because they're the kind of bacteria that you could eat, have dinner with, these bacteria are there to protect us. They're the majority, the vast majority. They're the ones that help destroy and degrade materials that we put in the earth, and they bring dead material back to create substances that live people and live things can grow on. So they're a recycling industry, so to speak, which is alive and provides us with all the nutrients we need in some way, shape or form.

Judy:

Well, yeah. They're used to clean up oil spills, right?

Dr. Levy:

Yes. Correct.

Judy:

I didn't realize that good probiotics, the good bacteria in the intestine actually produce vitamins. What vitamins do they make?

Dr. Levy:

Well, vitamin B-12 is essential for us, and we need bacteria in our intestinal tract to produce that vitamin for us, and we absorb it. That's why some people who are on large amounts of antibiotics often are vitamin B-12 depleted.

Judy:

Interesting. Interesting. Well, how are antibiotics made so that they work only against bacteria and not viruses?

Dr. Levy:

Well, they're put through tremendous tests. Well, let's start from the beginning. First, you want an antibiotic to be able to stop the growth, inhibit the growth or kill a bacteria. The virus really is a totally different entity, and the antibiotics that we use destroy a feature of the life cycle of a bacterium so that it can't actually multiply. It can't actually grow. Whereas the virus, as we discussed earlier, it's inert. All it can do is go into a cell and use its machinery and then burst the cell. So there are special chemicals that treat viruses, these are called antivirals, but they're different from antibiotics which are developed to treat bacteria.

Judy:

So when were antibiotics actually discovered? For a lot of people there's never been a world without them, but they're actually only a few generations old. Isn't that right?

Dr. Levy:

That's absolutely right. It goes back about 60 years. The first kind of an antibiotic came out in the mid 30s was sulfonamide. This was a synthetic, something chemists made, but it acted against bacteria. But the true antibiotic in the sense that it was made by one biologic creature and is able to inhibit another - that's what is anti-bio - was really penicillin made by a mold, a fungus. And that was discovered serendipitously by Sir Fleming and then moved into production by Florey and Chain and Fleming to become an antibiotic in the early 40s.

Judy:

So during World War II.

Dr. Levy:

Yeah. It made a big impression in World War II and, really, antibiotics are touted as the reason we had less casualties in that war than in previous wars.

Judy:

Previous wars. Do you know roughly how many lives have been saved since antibiotics were discovered, and by antibiotics?

Dr. Levy:

You know it's millions. You just know it's millions. And you know, before we had better hygiene and sanitized water and all of that, antibiotics filled that need because hygiene wasn't optimal. With the increase in hygiene and attention to hygiene, certainly we've reduced infections, but we've also increased medical technology in terms of treatments of cancers and transplants and all. So we leave people more vulnerable to infections, and they can die from those. So we're evening it out, but I would clearly say that in the past more lives were saved by antibiotics than they are today.

Judy:

Well, how were serious infections treated before we had antibiotics? Did you just sort of pray or what?

Dr. Levy:

Well, you know there are things called leeches.

Judy:

Ah, yes.

Dr. Levy:

These kind of natural remedies were passed down from generation to generation in almanacs, the old-fashioned chicken soup. And when I was doing a study for my book, I found there was even a recipe for frog soup claiming to help you get over what was then called coryza, but it was a cold, really. So, yeah. No one was willing to accept sickness, so they were always looking for something to do. And this goes back thousands of years, even to Egyptian times where they were using all different kinds of medications and medicines to treat infection.

Judy:

Well, did the leeches really work?

Dr. Levy:

You know, in certain diseases leeches do work. And I know you're going to ask me which ones.

Judy:

Well, I thought they were good for reducing swelling and stuff.

Dr. Levy:

Yes. But they also excrete certain enzymes that can in fact be helpful. And they're used still today in certain countries, and I think in developed countries they use them.

Judy:

Yes, I know. I've seen them at work. Kind of gross, but whatever works.

So how many different kinds of antibiotics are there today?

Dr. Levy:

Well, you know, you classify them by structure. There are hundreds of different ones. If you look at their structure, they're different, but you can then classify them structurally and say there are about 15 to 20 different classes, and each class might have 20 or 30 different antibiotics, so you add them up. But pertinent to the discussion tonight there isn't really a single antibiotic out there that a bacterium hasn't learned to become resistant to it.

Judy:

We're going to get to that very, very soon. But most of the antibiotics out there, they are specifically built to kill a particular class of bacteria, right?

Dr. Levy:

Right.

Judy:

Or are there some that are so broad spectrum they will attack anything?

Dr. Levy:

Well, that's how they're often separated. Those that are narrow spectrum, which will hit a kind of bacteria through cell walls stained with a stain that Sir Hans Christian Gram invented at the end of the 19th century. We call them gram-positive, and staph is one of the Gram-positive, and strep for strep throat is a Gram-positive.

But then we have what is called the broad spectrum, and that includes generally all the Gram-positives and then the Gram-negative. These are the ones that don't take up the Gram stains, and they often are more difficult to treat because they have more resistance intrinsic, that is, they're born that way. But among those common ones probably known by those listening today would be E.coli, which causes urinary tract infections, and Pseudomonas, which is a severe infection [sometimes] of patients who are on chemotherapy because it's so resistant. And it really infects and virtually terrorizes these patients who are already down and out.

Judy:

I can imagine. So let's talk about resistance. What is it, and how do bacteria become resistant to antibiotics? That's kind of the nub of what we want to talk about tonight.

Dr. Levy:

Well, resistance means that the bacterium is no longer susceptible to the action of the antibiotic.

Judy:

Right.

Dr. Levy:

It's often confused, people will say, "Well, I had an infection but I was resistant." You're not resistant. It's the infection that was resistant.

Judy:

Bacteria.

Dr. Levy:

It's the virus or the bacterium. All right?

Judy:

Yes.

Dr. Levy:

It will no longer succumb to the antibiotic. How? Well, it could sustain a mutation that is a change in a protein and the very protein that the antibiotic blocked.

Judy:

A mutation in a gene that makes the protein, right?

Dr. Levy:

That's correct. So that now makes the bacterium resistant to that antibiotic because the product of the gene that's been mutated is no longer affected by the antibiotic. So it's resistant through mutation and all its progeny will be resistant because they are an exact duplicate of the resistant one, and if you use the antibiotic it won't touch, and these bacteria and all their progeny will grow.

Judy:

So as with the rest of evolution, these mutations come about by chance, but the bacteria are multiplying so fast that there are a lot of mutations that can occur, and as soon as the one that changes the protein that the antibiotic goes against emerges, then we're cooked, basically.

Dr. Levy:

You're right. There are so many millions of bacteria out there, and they're in colonies of at least like a hundred million that you can see them as a little button on agar , then what you're seeing is one mutation in there, and you add the antibiotic, all the other bacteria are killed, but that one that's resistant now can multiply, doesn't have any competition for nutrients, and it becomes the selected, we say, survivor of that treatment.

Judy:

Right.

Dr. Levy:

So that's the common way, but there are plenty of other ways.

Judy:

What are the other ways?

Dr. Levy:

You can get the resistant gene or the mechanism from another bacterium in the environment, sort of like trading playing cards or something, you know. Your one bacterium are covering this surface, and you come up against another bacterium and you receive as a gift a piece of DNA which contains a resistant gene. Now, if you don't have the antibiotic there, that exchange is lost in that single bacterium that got that single transfer and it's outnumbered by all the others. But if in fact you add an antibiotic to that environment, whether it's the person or the table top, then that single exchange is now amplified because -

Judy:

The bacterium that gets that drug-resistant gene has a huge advantage over all the others.

Dr. Levy:

It survives, yes.

Judy:

Yeah. Well, this makes you think that why isn't the problem of antibiotic resistance even worse than it is? It sounds like we don't stand a chance.

Dr. Levy:

Well, This is complicated - in most instances in biology, you get resistance or change by mutation. Here a single exchange can give you resistance to five or six antibiotics all linked together in one piece of DNA that gets exchanged. And, yeah, you say, "Well, why don't we have more problem?" Well, in some respects it's because we believe the resistant ones are just a little bit less able to fit in the environment, in different environments. So they don't quite make it when the antibiotic is not there.

Judy:

You don't mean fit physically.

Dr. Levy:

Fit in terms of their physiology, being able to live and out-compete with other bacteria, because, you know, there are a lot of bacteria out there competing for the same space, whether it's your intestinal tract or your skin or the back of your car.

Judy:

So they don't fit as well in the sense of the survival of the fittest. They're not among the fittest.

Dr. Levy:

That's correct.

I was going to say that's one thing, and the other thing is that fortunately up to now we've been always a few steps ahead of bacteria in getting new antibiotics, so if they were resistant, we had a drug to treat. That situation is not so now, and therefore we are looking to preserve the strength of the antibiotics we have now and hope to find a few new ones, but the industry that's looking into it is much, much smaller. That is, large pharmaceutical companies are no longer in the discovery field.

Judy:

Why not?

Dr. Levy:

It's claimed to be not as profitable because people get an infection they get cured of it; they don't need that antibiotic anymore.

Judy:

But people are getting sick all the time. New people are getting sick.

Dr. Levy:

Right – but think about it. If you are on a lipid-lowering agent or a high blood pressure lowering agent, you're on it for your life, you as one person. So you, already you're using a lot of that medication. If you get a sinus infection, then what you'll do is you'll take it for hopefully three to five days and be done with it.

Judy:

Okay. So they work too well from the drug companies' point of view.

Dr. Levy:

Yes, although I have to tell you that there are plenty of very good antibiotics out there that are making very good money for the companies, and it's a question of how much do you want and also how much do you want to invest in discovering, because all the best antibiotics - well, easiest-to-find antibiotics, the so-called low-lying fruits - have been taken. So you've got to work harder.

Judy:

Tell us a little bit about MRSA. What do those letters stand for, and how prevalent and scary is this? We read in our intro that the latest report is that 19,000 Americans died from this in 2005. What is this?

Dr. Levy:

MRSA is a bacterium. It stains with a Gram stain, so it's Gram-positive. It's M-R-S-A, the "M" stand for "methicillin" or "multidrug." "R" stands for "resistant," and "S-A" stands for "staph aureus." So you have staph aureus that we carry in our nose, on our skin, which is not necessarily resistant and not MRSA, although about 9 to 10 percent of people are carrying MRSA. They don't come down with the disease but they carry it in their nose. And these strains of bacteria are known because they resist a synthetic penicillin drug called methicillin, which was invented when staph aureus became resistant to penicillin, which happened fairly quickly.

Judy:

When did that happen?

Dr. Levy:

It happened in the early 60s.

Judy:

Oh, so it's been a long time?

Dr. Levy:

Yeah. So methicillin came out. It was able to handle the bacteria that was resistant to penicillin and made its headway, did well, and became a drug of first resort for staph aureus until strains emerged, first in, actually, Northern Europe and then in the United States and wasn't evident and then came back with a vengeance recently, which are methicillin-resistant staph aureus, M-R-S-A. The point I made earlier is that the "M," which originally stood for methicillin, can now stand for multidrug, because these bacteria are not only resistant to methicillin and penicillin, but they're resistant to tetracycline, chloramphenicol, streptomycin, many, many different antibiotics, which makes them much more worrisome, much more difficult.

Judy:

Yes. Scary. Well, how scared should we be?

Dr. Levy:

I think that the alert is on. I think that people who are living a normal life, keep up with exercise and keep their health and wash when it's appropriate, that is before they eat, and so much of bacteria infections are passed from hand to mouth, that they aren't going to face this kind of problem. On the other hand those that do are finding that this MRSA is a very unpleasant bacteria. It doesn't mean that we can't cure the majority, but there are cases that there are individuals who will and have died.

Judy:

Well, how did we get into this predicament, not only with MRSA, but other types of drug-resistant bacteria? Have doctors been over-prescribing antibiotics or are patients clamoring for them too much, or is it just nature doing its thing?

Dr. Levy:

Well, it's a little bit of everything. I think the first thing is that if you don't have the antibiotic, the resistance isn't going to make one bit of difference. You need to have the antibiotic and the resistance together to have a resistance problem.

Judy:

You mean in the same person?

Dr. Levy:

In the same person, in the same environment, in the hospital, in the home.

Judy:

Okay.

Dr. Levy:

So think about it. If I'm using a new antibiotic comes out, resistance isn't there. You can use it until you select for those that are resistant, and in the meantime it's not doing any harm. What has happened is what you were alluding to. Doctors have over-prescribed, patients have stockpiled, patients have begged and clamored for the drugs. They've used it without prescriptions when they have…

Judy:

How do you do that?

Dr. Levy:

You have leftover drugs. Put in your medicine chest and you think, oh, this is what I had before; I'll just take a few. And it's probably a viral illness, and you're wasting the antibiotic, and you're selecting resistant bacteria in your own environment.

Judy:

You mean in your own body?

Dr. Levy:

Yeah - well, and more than that. There are many studies out. We talk about the ecologic effect of antibiotics. There is a wonderful study showing, came out of England from a dermatology clinic, where patients who were taking an antibiotic for 10 to 15 days for acne, and they looked at the kinds of bacteria, not dangerous bacteria, on the skins of these people taking the antibiotic and their house partners or mates or children. And dramatic increases in resistance were found on the bacteria in the bacteria on the skins of people sharing the household even though they were not taking the antibiotics.

Judy:

Wow.

Dr. Levy:

This is the antibiotic sort of corollary of secondhand smoke.

Judy:

Yeah.

Dr. Levy:

Right?

Judy:

Yeah. That's kind of scary. Well, what illnesses genuinely deserve to be treated with antibiotics?

Dr. Levy:

All bacterial illnesses should, unless it's a little pustule, your hair follicle gets infected. Generally if you wash it with soap and water or a little alcohol, it's going to get better. But I think that you need it for strep infections, certainly strep throat. You need it for certain ear infections which are bacterial, not the viral kind. You need it for urinary tract infections. You need it for blood infections. You need it for lots of pneumonias of different types. So, yeah. It's life-saving in many common illnesses and then in those we see in the hospital where patients are really at risk of getting a bad infection. Plus, their defenses are down.

Judy:

Well, is there any way for doctors or patients to tell, especially with upper respiratory or ear infections, when it's a virus and when it's bacterial? Because I've gotten in arguments with my own doctor. I get a cold and the cold stops everything up, and then I say it becomes bacterial, and she says, oh, it's probably just a virus, and we go back and forth for three weeks while I feel crummy. Is there any way to tell?

Dr. Levy:

Not yet. Not yet. There are some new tests coming out which claim - I think there's one already licensed in Europe - which can distinguish whether you have a virus or bacteria, not which kind of bacteria.

Judy:

Well, if you could just tell that difference.

Dr. Levy:

That would be a big advantage. There's some based on different proteins that you could have in the blood. And this is very exciting.

Judy:

There's no Q-Tip thing you could stick up your nose and put it on a microscope slide and tell the difference?

Dr. Levy:

No, because, first of all, in your nose you've got a lot of bacteria that are good. And some of the good, like staph aureus might be causing your infection because, I think your doctor is right, it's largely a cold. But be that as it may, I think that we do need diagnostics. That's really what you're moving toward. We need diagnostics to know is it bacterial, is it viral? Is this bacterium going to be susceptible to the antibiotic or, better yet, can this test tell me to what antibiotic this bacterium is resistant?

And there are movements in the diagnostic field, and many of the large companies move in that direction. I do know that the Alliance For the Prudent Use of Antibiotics you mentioned earlier, an international organization, is actually running a symposium in two weeks in diagnostics, has been working with diagnostic companies to be able to demonstrate where and how better diagnostics can improve our selection, our choice and our outcome of an antibiotic therapy.

Judy:

Well, listen I'll be calling you. I'll write a column about that. That would be wonderful, especially if it's an over-the-counter thing that people can do themselves and not bother the doctor if they don't really have a bacterial infection.

But I wanted to talk to you about another article that's in this week's Journal of the American Medical Association, and that's from doctors in Rochester, New York who have identified one of these super bugs which are resistant to a lot of antibiotics. It's called the 19A strain, and it causes ear infections, and it seems to be resistant to all the pediatric antibiotics. It can be killed by an antibiotic called Levaquin that's approved for adults, but that has a warning on the label saying don't use it in kids. So I would think for a lot of parents this could be very scary because everybody knows kids get ear infections all the time, and it's really hard to know when to give them antibiotics and when not to. Tell us what you know about this situation.

Dr. Levy:

Well, I think this is nature telling us something that we knew but we didn't expect it to appear so rapidly. The 19A is a strain of the pneumococcus which causes pneumonias and ear infections. And to the credit of science and immunologists the vaccine, called the 7-valent vaccine, was created, and lots of kids and adults have been vaccinated against seven different types of the most invasive kind of this pneumococcus. And what it has done is greatly decreased the kinds of resistant pneumococcus and the worst fate of a pneumococcal infection, that is, inflammation and disease of the brain called meningitis. That's been wonderful.

But nature abhors, as I say, a vacuum. And here you've removed these bacteria from the mouth, nose, and they often lie there without causing problems, and another strain, which was not part of the original vaccine, was able to take over. And it turns out that it's not only drug-resistant, but it also is invasive. I've not seen it associated with meningitis, but I do know it's been involved in ear infections.

Now, most ear infections are viral, so whether you have 19A or what, the most likely cause of an ear infection in kids is a viral illness which will get better in 24 to 48 hours. So then what? Well, if the child has been vaccinated, then the clinician should be told, "My child has been vaccinated," and therefore the suspicion that it might be one that's resistant would appear. But in the normal sense, no.

Well, that's not saying we shouldn't vaccinate because what I said was the vaccination has really reduced the incidence of meningitis, which is life-threatening and much more serious than the ear infection.

Judy:

Yeah, we just had a case here in Massachusetts where a college student had been vaccinated against meningitis and got it and died anyway.

Dr. Levy:

Yeah, that's a different organism. Go ahead.

Judy:

We have a couple of e-mails that have come in. One is from Susan from Dallas, Texas. She writes, "I developed an allergy to penicillin in my early 20s. My question is why would I suddenly become allergic to a drug after years of tolerating it? Also, I'm worried that since I can't take penicillin, I will eventually run out of effective treatments. Is this a rational fear?"

Dr. Levy:

Not really. I think that many allergies appear at different ages. Some you get early and you lose, some you get later. And this has to do with how your immune system may be seeing penicillin, and it may be because a portion of the drug resembles another - we call them antigens, another protein your body saw and so you what is called a cross reaction.

But penicillin is really only one of 15 or 20 different classes of antibiotics, and there are plenty more that would be available for you to use, Susan, if you need them.

Judy:

And we have another question that I like a lot because I am a fellow chronic sinus infection sufferer. This is from Tim in San Diego. He writes, "I had a year of chronic sinus infections. During that time I was constantly on antibiotics. Eventually the antibiotics stopped working after only a few days, and the infection would return. My doctor had to keep switching me to another drug to get the infection under control. My illness got so bad that eventually I had sinus surgery. Luckily, the surgery solved the problem, and I haven't had an infection since. What advice would you give someone who's getting diminishing results from antibiotics and is considering surgery or other options?"

Dr. Levy:

I think you need a good ear, nose and throat specialist to look at you. There are two things. One, an infectious disease specialist would know about the kinds of bacteria and the kinds of antibiotics that can be used, because, again, in many instances these are viral infections, in many instances they get better on their own. But in certain individuals this could be structural, that is, your sinuses are not draining correctly, and therefore, you're set up for an infection which will come and, when you treat with the antibiotic, it does get better, I think that's clear evidence that it's bacterial. But it may come back because of the fact of how your sinuses are arranged. And I think a good ear, nose and throat physician will be able to tell you, yes, this might be it. But certainly no one wants to go into surgery right away.

Judy:

No. I can vouch for that. Maybe we should have a show on sinuses. But what infections should not be treated with antibiotics?

Dr. Levy:

Well, we've been pushing it all during this show here, Judy. It's viral, viral illnesses.

Judy:

Right.

Dr. Levy:

They are not affected by antibiotics, and what you're doing is just helping the bacteria that are resistant to have an edge over those that are susceptible whenever you use it, whether it's on the skin of your body or in your intestinal tract or the bacteria in your colon. All you're doing is you're wasting the drug, and you're creating a resistance environment.

Judy:

So who does that harm? Does it harm you, the person who took the antibiotics needlessly, or does it harm sort of the whole ecosystem of bacteria, or both?

Dr. Levy:

Antibiotics I've said many times are societal drugs. Think of it that way. There is no other drug like them. No other therapeutic like them. Most therapeutics, not all, are addressing an individual problem, and it's the heart or the kidney or the brain or whoever. Antibiotics are treating an invader of your body. Not something wrong with your body. It's something that came in and is hurting your body. And when you create resistant forms of that bacteria - or if you're using viruses, the same - you are then creating a societal menace. You're contributing to bad health in the environment in which you're living, whether it's your home, your community, your hospital. So that's why there is a consequence which is societal to everyone's use of an antibiotic. So you really want to use it when you need it.

Judy:

And you want other people to use it only when they need it.

Dr. Levy:

You certainly do. People are saying, "Oh, I have antibiotics, carry them all the time. I take a pill every time I feel my nose itch." Come on.

Judy:

Yeah. You do have to suffer. I read that there's tiny little critters called phages, p-h-a-g-e-s, which is actually a kind of virus more or less, and that they are starting to be used to combat bacterial infections. What are phages, and how might they work against bacteria?

Dr. Levy:

Phages are nothing more than viruses of bacteria.

Judy:

The viruses of bacteria you say?

Dr. Levy:

Yeah. They are much smaller. When we speak about viruses in terms of human health, we're thinking of viruses that invade human cells.

Judy:

Right.

Dr. Levy:

They're the kinds like influenza virus and other viruses, flu virus. They infect human cells, destroy them, cause disease, etc. When we think of phages, we're talking about the fact that these little tiny single-cell organisms (bacteria), a thousand-fold smaller than the human cell, has its own viruses. And these viruses, for want of a better name largely because they were discovered by d'Herelle in the early part of the 19th century, are called bacteriophages or phages, and phages are bacterial viruses. They do to bacteria what normal viruses do to human cells. That is, they go in, they take over the cell, they multiply, they get coats put on top of them, the cell bursts, and they go out and look for another bacteria.

Judy:

So bring them on. Where are they?

Dr. Levy:

Well, the point goes back to the days of "Arrowsmith" and other books of that nature where phages are now beginning to be considered as therapy because if they can seek out bacteria and they don't really work against people, then they're the perfect antibiotic. Well, the problem is that, one, they need to find a receptor on the bacterial cell in order to get in, and it's easy for the bacterial cell to lose that receptor, so the phage wouldn't work.

So against that are phage companies now that are making groups of phages. And in Russia, phage therapy is really almost main vine, main stream. It's done. They put it into the bloodstream, which to me is pretty impressive. I think in this country we're looking at it in terms of food production, preventing bacteria from contaminating meats and other food products. After all, phages are not going to harm us. They're protein. They're infinitesimally small, you can't see them. So they get rid of the bacteria, so much the better. You don't have to radiate. You don't have to worry about passing resistant forms or even dangerous forms from one animal to people, or vegetables to people.

So there are companies looking at phages to treat infections of people, like MRSA. There are those looking at them to use in the environment, to use in agriculture or in animal husbandry.

Judy:

Well, that's a perfect segue to my next question which is the use of antibiotics in livestock. Why do farmers give antibiotics to their animals?

Dr. Levy:

Well, in the '40s and '50s there was a discovery that the leftover shells of bacteria that made the antibiotic tetracycline, when given to chickens, would allow them to grow faster and better for the same amount of protein. It was thought to be a vitamin. It was the days when new vitamins were being discovered, and it was a nutritional factor, so to speak.

Well, it turned out that when they tried to isolate that new nutrition factor they discovered - and they ended up with it in their hands - that it was nothing more than trace amounts of antibiotics that the bacteria had been so-called cleared of in the production of tetracycline. But there was enough left that when the animal ate some of this mash made up of the shells of these bacteria that there was enough antibiotic in it to give them a growth benefit. Well, what is that growth benefit? It was thought at first to be a growth factor, but it's not. What it is, it's the antibacterial activity at a low level in the intestinal tract of the animal.

Judy:

Why would that give it a growth benefit?

Dr. Levy:

Well, it turns out that when they looked at the lining, the inner linings of the intestinal tract where nutrients are absorbed, they saw that the antibiotic-treated animals had a thinner inner membrane.

Judy:

Lining.

Dr. Levy:

Lining. So - I'm telling you it's all supposition. A lot of this has not been studied. And in fact they soon became aware, as more hygienic measures have been put into animal husbandry, that they weren't working at the low, low levels they were originally. It had to be high-level or you didn't see an effect because, in fact, the real benefit from these drugs was in their elimination of sort of an underlying kind of low-level kind of infection that may not have been life-threatening to the animals but was causing less protein utilization and less growth.

It's common in the United States but it's less common than it was. In the cattle industry, they've more or less removed all antibiotics, and they're using another kind of product called monensin. The chicken industry has more or less left it. They are still using antibiotics for therapy. But there are still some farmers and there are still some farms where antibiotics are used in what is called "growth promotion" activities which is low levels in the feed. That soon will end because our own FDA is looking into the issue, and there's a lot of concern, which started 30 years ago let me tell you.

Judy:

Yes, this is an old issue.

Dr. Levy:

An old issue that I've been involved in for the last 30 years.

Judy:

I know.

Dr. Levy:

Trying to teach that you don't need it. And Scandinavia has certainly proved that and the European Union. The European Union has now banned all antibiotics as growth supplements. They are no longer able to be used, and they are not suffering in terms of the food they're bringing to market.

Judy:

No. In fact, having recently returned from Europe and having some wonderful steaks, is it possible that the steaks taste better over there because of the lack of antibiotics?

Dr. Levy:

No. I don't think so, but we'll bring you down, Judy, you can testify.

Judy:

Right. Right.

Dr. Levy:

Yes. It's another advantage.

Judy:

Well, what was the potential or actual harm for humans in eating animals laced with antibiotics?

Dr. Levy:

Well, it's interesting. It was not the animal that was the problem, the fact that there might be antibiotic left over. After all, we started by saying these are very low levels of antibiotic, and there is a regulation by the Center of Veterinary Medicine of the FDA that if you had an animal on antibiotics you had to go through a waiting period where you couldn't sell the beef for two weeks or whatever and they know it's out of the system. But you did not get rid of the other consequence of that use which is, to many of us, even more consequential, and that is the resistant bacteria.

So the farms using these antibiotics, we saw this in the '50s, the '60s, the '70s, the '80s, that the farms that were using antibiotics for growth promotion had lots, and I mean lots of resistant bacteria on the farm in and associated with the animals, associated with the people who were working on the farm. We did a study in the mid '70s that showed when we took a naive farm and just introduced chickens and antibiotics to half and not the other half that those who got the antibiotics soon were breeding resistant bacteria, and the people who were working on the farm picked up these resistant bacteria and they also were affected by the antibiotic in the environment. So it became an ecologic issue. And this was published in the New England Journal in 1976 and still, you know, the practice is going on. So I'm happy that it's out of certain industries but not totally.

Judy:

Well, I understand that the National Institute of Health published an article recently in the journal called Environmental Health Perspectives, saying that the routine use of antibiotics in livestock is definitely contributing to this rise of antibiotic-resistant germs in humans. Is that true?

Dr. Levy:

Yeah. Yeah. But it depends on which. So if you look at resistance, total resistance, yes. If you look at particular bacteria - for instance, you could have said to me, "Well, gee, is MRSA a problem from the chicken?" And I'd say absolutely not.

Judy:

Why not?

Dr. Levy:

Because MRSA doesn't live with chickens.

Judy:

Oh.

Dr. Levy:

But one could argue that some of the resistance that it's picked up, it picked up from other bacteria that did come from chickens. We want to make an argument. We can say that the whole environment is one big genome consisting of one big, huge chromosome of all bacteria and an antibiotic zone, which is all antibiotics shared in all different environments, so, you know, is it really fair to say this comes from one or comes from the other?

So I think it's fair to say that most of the intestinal diseases, diarrheals, and so forth with resistance, come largely from animal use. And the total numbers of bacteria that are resistant are much greater in my opinion in the animal husbandry area than they are in people.

Judy:

Well, I've read that in Denmark where antibiotics have been banned for farm animals, there have been no adverse consequences for farmers economically. Do you know if that's true?

Dr. Levy:

Yeah. You're reading exactly what I'm reading. And actually, The Alliance for Prudent Use of Antibiotics gave an award, the Leadership award to the Danish Institute for instituting and overseeing that. We also gave it, by the way, to McDonald's because they made an announcement several years ago at the time when the award was given that they were no longer going to buy their meat from distributors who were using antibiotics for growth promotion.

Judy:

That must have had a huge effect.

Dr. Levy:

It was impressive - well, I think it gave strength to many of us who have been on that bandwagon for so long. And I think, one, the fact that it's working in Europe, it should worked here too. The fact that the European Union has now banned it, that's all the European Union. Three, a company of the stature of McDonald's acknowledges that there's a problem by saying, —"We're telling all of our distributors or those where we get our meat that we don't want this and we won't buy if they do." I think all that is building up to where the Center of Veterinary Medicine, the FDA itself will--

Judy:

Yeah, that's a lot of economic pressure.

Dr. Levy:

It's going to follow suit, yes.

Judy:

Yeah. You touched on this briefly before, but are there new antibiotics in the pipeline that might be able to fight these super bugs?

Dr. Levy:

Fortunately there are. The MRSA problem has been going on for maybe even decades now. It's gotten worse. But it was handled largely by an antibiotic called vancomycin. It's an antibiotic of last resort. And there was a lot of concern because there were strains of MRSA that were becoming less susceptible to vancomycin and on the road to resistance. So we needed new drugs, and we were afraid that we would have a vancomycin-resistant MRSA before we had new drugs. So we got new drugs before, just made it.

And those drugs - one was a streptogramin, another is linezolid, another is daptomycin, from companies that produce them, and they are handling MRSA and other Gram-positive type infections in terms of during disease even though these organisms are resistant. So this is helpful. Yes, there is a little resistance already emerging to these drugs, especially if you use them for long periods of time but in general they're still quite effective.

On the other hand, the so-called Gram-negative bacteria that we mentioned earlier in the show there are no new drugs for. There are some out there, but coming down the pipeline, there are very few. There is a drug Wyeth put out called tigecycline, which is a tetracycline derivative which has activity against Gram-positive, some Gram-negative. The pharmaceutical company that I started called Paratek Pharmaceuticals has a new antibiotic which is finishing Phase II, but that means it's still a couple of years from entering the clinic, and it also is broad spectrum and able to hit some of these bad Gram-negative.

Judy:

But overall there's a decline in new antibiotic development.

Dr. Levy:

Overall, it's bad and the reason is, well, it's twofold. One, it's more and more difficult to find the antibiotic because the antibiotic has to be so-called toxic to the bacterium but nontoxic to people. And what we are finding sometimes is you have a great antibiotic only to find that -

Judy:

It kills the person.

Dr. Levy:

When you test it in people, it causes all sorts of damage so you've got to scrap it. And that gets very frustrating.

Judy:

But also you said earlier that drug companies aren't putting the money in.

Dr. Levy:

Well, if it was easy, they would, but it's hard. And so the drug companies are saying, "Our stockholders want to have a return on their investment, and antibiotics is just not going to give it to them fast enough, so we've left the antibiotic field." And most - if there were 15 companies, there are now five. I mean it's that kind of drop, and large.

Judy:

Yeah.

Dr. Levy:

So the void is being taken up by small biopharmaceutical companies, and they are doing the discovery. So they discover a new antibiotic, they do all the testing, they take all the risk, and then big pharma, as they are often called, can then decide to step in and take the…

Judy:

Make it and distribute it.

Dr. Levy:

Make it and distribute it and do all the very expensive testing in people. But even that's not evident. I mean, I think there's a lot of interest in trying to provide incentives to big pharmaceutical houses these days to come back into the field. I mean, they actually got rid of their whole infectious disease units, so it's going to be costly to bring them back. They'll probably do it by buying up some of the smaller companies that are already out there.

Judy:

What about taking probiotics like acidophilus bacteria, the good bacteria, to fight bacterial infections? I actually have a friend who had a serious infection after an appendectomy in a third world country, and once she got back here no antibiotics really seemed to work. And the doctor told her to eat lots of acidophilus tablets and yogurt, and she got better. Tell us about this. Is this a solution we should all try a little more?

Dr. Levy:

You're talking to someone who really likes the concept of probiotics. In many respects, phages are a probiotic because they're really a live other entity that really…

Judy:

Fight the bad bacteria.

Dr. Levy:

It's still biologic. It's not chemical.

Judy:

Right.

Dr. Levy:

I think that probiotics in terms of lactobacillus is one that has been shown that - there's a couple, some on the market actually - that have been shown in clinical studies to really work in diarrheal diseases, in certain other diseases caused by bacteria of the intestinal tract. Very impressive. Obviously, I'd love it. Why not control disease with biology rather than chemistry? For one, it's the natural way of doing it. Bacteria and other organisms are competing all the time. And, two, you don't expect to get resistance, so it's great.

Judy:

What about for not intestinal things. I mean, if you had a skin infection could you slap some yogurt on it?

Dr. Levy:

I haven't, no. I've seen honey being used for that, and phages. Maybe they're going to think about it, but no, no I haven't.

Wow. And is there anything along this - I don't want to call it naturopathic - but along this kind of biologic line for sinus infections? I mean, can you put yogurt up your nose?

Dr. Levy:

I wouldn't.

Judy:

Honey?

Dr. Levy:

No, I would not advise it. This is in wounds where there are open wounds and there have been studies where they put honey in there and that protects it while the wound is healing. I wouldn't say to go smear myself with honey. I think we'd have a lot of insects, flies, and there would be more problems than solutions.

And I think the reason it's of interest is that maybe certain products out there that we use all the time are potentially useful, but we don't do it. And I think the probiotics are at least something that's becoming more acceptable. But it's far more advanced in Europe than it is in the United States.

Judy:

We don't have tons of time left, but I want to ask you a question about infections in hospitals. I've read that hospital infections would decrease if male doctors, or maybe female doctors, but mostly male doctors stopped wearing neck ties.

Dr. Levy:

Well, you know, I saw this - I don't know if it's a decree but I think it's one of the hospital associations saying that they're going to now set up a new dress code for physicians. You know, in my day and still the way I do it, I mean, I feel it's respectful to wear a coat and tie or a tie and a white jacket when I go into the hospital to see patients. Well, now they're going to ask that you have no necktie, you have no jacket, you have a short-sleeved shirt and you wash your hands, of course you have to. And that way - no ties, of course - you will not be bringing these bacteria around.

I have not seen the studies. I've seen the studies that say, oh, you can pick up bug X on the necktie and whatever, but the question is who has studied, pilot or what-all, to show that this kind of activity reduces the transfer of infections? Maybe it exists, but I haven't seen it. But I think it's in line with where we're headed, which is to control the spread of infection in the hospital, and any way we do it the better.

Judy:

And one last question. What about hand sanitizers like Purell? Do they really work for viruses and bacteria?

Dr. Levy:

Yeah. And I must say that alcohol-based sanitizers, and we use them in the hospital, they're in a dispenser. And we like them because it's not easy to be able to wash your hands in between patients. It takes more time. This way the alcohol dispenser is there, you take it, you put it on your hands, it's gentle, and it effectively removes many, many - thousands and millions of bacteria from your hands so it reduces the spread. Exactly what I'm saying, reduce the spread, and it has been shown to do that and hands have been looked at and so forth. And it's replaced the soap and water need, and it's been a blessing, really.

Judy:

Well, that is great. I want to thank my guest, Dr. Stuart Levy. He's the director of the Center for Adaptation Genetics and Drug Resistance at the Tufts University School of Medicine in Boston and the author of a very good book, "The Antibiotic Paradox: How the Misuse of Antibiotics Destroys Their Curative Powers." So, Dr. Levy, thank you very much for being with us.

Dr. Levy:

Nice to be with you Judy again, and all the best.

Judy:

Great. And thank you, listeners, for joining us. Until next week, I'm Judy Foreman. Good night.

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